The invention relates generally to retail cheese products, and particularly to methods and apparatus for producing retail cheese products of controlled weight.
In the manufacture of bulk cheese products, large blocks of cheese, nominally weighing, e.g., 40 lbs., 240 lbs., or 640 lbs., may be formed using a tower system. Tower systems can allow for the introduction of cheese curds and whey into the top of the tower, the extraction of the liquid whey from the cheese curds, and finally the withdrawal of solid cheese from the bottom of the tower. Guillotine blades may operate to sever the cheese into blocks as it emerges from the bottom of the tower.
Such large blocks or barrels of cheese generally are not of precise weight, and are generally not intended for retail sale. Instead, the large blocks typically are divided into smaller chunks, slices, or other portions.
When packaged for retail sale, the weight of the product must be accurately set forth on a label. Random weight products are produced without precise control of the weight of the product, then weighed and sold at a price dependent upon the weight. Exact weight products, on the other hand, are made within close tolerances so that they may be produced at a weight of e.g., 605 gm xc2x15 gm, and labeled with a predetermined xe2x80x9cexactxe2x80x9d weight, e.g., 600 gm, rather than having to be labeled with different xe2x80x9crandomxe2x80x9d weights. Production of exact weight products greatly simplifies packaging, labeling, and pricing.
In the past, manufacture of exact weight natural cheese products for retail sale typically has entailed generation of substantial quantities of trim or offcuts having reduced value. For example, dividing a 640 lbs. barrel of cheese into retail portions may result in 18 to 24 percent trim or offcuts. Thus, there has been a need for an improved method of producing exact weight natural cheese products.
Production in cheese towers generally has not been compatible with exact weight cheese production.
Pittelko, U.S. Pat. No. 5,209,943, discloses a tower with a discharge port in communication with a cheese receiving station. A pair of guillotine knife blades are disposed in communication with the discharge chamber at the base of the tower and form the support for the column of cheese as the tower is filled. After a predetermined amount of cheese has been deposited on the cheese receiving station, the guillotine blades operate to sever the cheese emerging from the tower into large blocks of cheese. However, the ""943 patent does not disclose methods or apparatus for making exact weight cheese products.
U.S. Pat. No. 5,243,900, also to Pittelko, discloses a cheese transfer system for receiving a column of cheese emerging from a cheese tower. The lower end of the cheese tower includes a chamber for maintaining the shape of a large cheese block cut from the column of cheese and introducing the large cheese block into a shipping container. A cheese platform assembly is provided beneath the chamber for guiding the column of cheese downward as the column emerges from the cheese tower. However, there is no disclosure in the ""900 patent of methods or apparatus for making precise weight cheese products.
In accordance with the invention, methods and apparatus are provided for producing portions of cheese products having precise weight using a tower system. As the cheese emerges from the tower, the cheese is cut into one or more consumer size quantities. The cut cheese quantity is then weighed, and the weight information is used to adjust the size of one or more subsequent quantities of cheese to be cut from the cheese emerging from the tower.
According to an embodiment of the invention, cheese curds and whey are placed into the top of a vertically-oriented cheese tower. The mixture is inserted into one or more forming tubes disposed within the tower and extending parallel to the longitudinal axis of the cheese tower. The forming tubes may be of rectangular, circular or other cross-section. The tubes have multiple perforations along their lengths to allow the liquid whey to be drawn out from the mixture by a vacuum, thereby forming a substantially solid column of cheese. In order to withdraw the liquid whey from the mixture, the tower may be sealed and its interior maintained at subatmospheric pressure.
A blade mechanism is provided at the lower end of the cheese tower for severing an end portion of the column of cheese. The blade mechanism may include a guillotine blade that is slidable between an extended position and a retracted position. In the extended position, the blade may be positioned to support the column of cheese. The extended blade may also function to seal the bottom end of the cheese tower. In the retracted position, the blade is positioned to the side of the cheese tower, allowing the cheese column previously supported thereby to move downward under the influence of gravity.
A pneumatic cylinder or other mechanism may be employed to move the blade back and forth, whereby a leading edge of the blade repeatedly severs the end of the cheese column to produce cut quantities of cheese.
A sizing gate mechanism may be positioned at or beneath the bottom opening of the cheese tower and below the blade mechanism. The sizing gate mechanism may include a sizing gate for supporting the cheese column prior to cutting, and subsequently supporting the cut quantity of cheese. Similar to the blade, the sizing gate is translatable between a retracted and extended position. When in its extended position, the sizing gate is preferably positioned to support the column of cheese when the blade is in its retracted position. When the blade moves to its extended position and severs the bottom end of the cheese column, one or more cut quantities of cheese remain on the sizing gate. While the column of cheese is supported by the blade, the sizing gate may be moved to its retracted position, allowing the quantity of cheese to move downward.
The vertical location of the sizing gate relative to the cheese tower may be changed using an adjustment mechanism. Changing the elevation of the sizing gate with respect to the cheese tower changes the spacing between the blade and the sizing gate, which corresponds to the height of the quantity of cheese to be cut from the cheese column. Accordingly, raising or lowering the sizing gate changes the size of the quantity of cheese to be cut from the cheese column.
A receiving conveyor may be disposed below the sizing gate and positioned beneath the bottom end of the cheese tower for receiving cut quantities of cheese when the sizing gate retracts. The conveyor may comprise a plurality of belts wrapped around two or more spindles. The conveyor belts and spindles may be configured to translate vertically between upper and lower positions with respect to a conveyor base that supports the belts and spindles.
A scale assembly is preferably disposed beneath the conveyor when the conveyor is in the upper position. The scale assembly comprises a scale support and a weighing grid. The weighing grid comprises multiple upwardly extending scale fingers. When the conveyor is in the upper position, the scale fingers of the intermeshing weighing grid are positioned below the top surface of the conveyor belts. However, when the conveyor is in the lower position, the scale fingers extend between and above the top surface of the conveyor belts for supporting cheese previously supported by the belts. The weight of the cheese then be measured by the scale.
The weight of the quantity of cheese may then be compared to a predetermined desired weight or range of weights to determine whether the cut cheese is within desired weight parameters. If the cut cheese weighs too much, the adjustment mechanism raises the sizing gate, thereby reducing the vertical dimension of subsequent quantities to be cut from the column. Conversely, if the cut portion weighs too little, the adjustment mechanism can lower the sizing gate to increase the vertical dimension and thus the weight of subsequent quantities.
In an embodiment of the invention, the conveyor moves to an intermediate position between the lower position and the upper position after the cheese has been weighed. The intermediate position may be aligned with a downstream conveyor to allow the conveyor to move the quantity of cheese to the downstream conveyor for direction to any subsequent operating stations. After discharging the quantity of cheese, the conveyor may return to its upper position to receive the next quantity of cheese to be cut.